the commercially available. [7] This is why generic modification methods for the metal sites in the frameworks are highly promising and thus desirable for the development of framework-based highperformance electrocatalysts for energy conversion and storage.To maintain the advantage of the frameworks for catalysis, it is essential that modification of the metal sites should be achieved without destroying the framework. However, selective, nondestructive modification of the metal sites is extremely challenging as most chemical modification on the metal sites also affects the metal-ligand bonding, which makes the framework more vulnerable. There have been many attempts to convert MOFs into catalysts by thermal processing, usually leading to framework decomposition and reassembly into nanostructures of metal oxides or metal-carbon composites. [8,9] Although good catalytic performance can be achieved, this approach results in complete collapse of the framework. In these cases, the high ordering and dispersion of the metal sites, which is the key advantage of frameworks for catalysis, is largely lost.In this work, we show that nondestructive activation of the metal sites in a framework can be achieved by using low-temperature (LT) air plasma. LT air plasma contains highly reactive oxygen species, including atomic oxygen and oxygen molecules in excited states. Importantly, these active species are nonthermal as the equivalent temperature of the ions, radicals, and excited atoms/molecules remain close to room temperature. [10] The combination of high chemical reactivity and low thermal effect allows selective modification of the metal sites without damaging the framework structure.The focus here is on the oxygen evolution reaction (OER) during the electrochemical water oxidation, which is the key reaction for many important applications, including sustainable hydrogen production, rechargeable metal-air batteries, and artificial photosynthesis. [11] The framework in our study is an Fe/Co bimetallic cyanide framework composed of cyanide bridged Fe and Co cations, which is a Co-based analogue to the well-known Prussian blue structure. Prussian blue analogues (PBAs) have been investigated as OER catalysts but only with moderate activity. [12] The highly reactive oxygen species generated by the LT-air plasma activates the metal sites in the Co-PBA for OER by oxygen bonding to the metal sites. Meanwhile, the key merit of high porosity and highly dispersed metal sites of the framework structures is retained due to the low thermal effect. The framework-based OER catalyst is featured for the very low overpotential of only 330 mV at high current densityTargeted activation of highly ordered and distributed metal sites in nanoporous frameworks is a generic strategy to develop high-performance catalysts. The key challenge is to achieve such activation without damaging the frameworks. Here it is demonstrated that atmospheric-pressure lowtemperature plasma generated in air improve catalytic properties of an Fe/ Co bimetallic cyanide fr...

Developing noble-metal-free catalysts for electrochemical hydrogen evolution reactions (HER) with superior stability in acid is of critical importance for large-scale, low-cost hydrogen production from water electrolysis. Herein, we report a highly efficient and stable noble-metal-free HER catalyst, which is composed of Ni and MoC nanocrystals supported on N-doped graphite nanotubes. This catalyst shows very low overpotential (65 mV in 0.5 M HSO at a current density of 10 mA cm with a Tafel plot of 67 mV/dec) and good stability for HER in acidic electrolyte, which is a promising noble-metal-free HER catalyst.